CAPZB rs10917469: What Your Genotype Means
The genetic variant rs10917469 is a single nucleotide polymorphism located near the CAPZB gene on chromosome 1p36. Research has identified a statistical association between this variant and variations in serum thyroid-stimulating hormone (TSH) levels.
What each genotype means
Typical baseline TSH levels
You carry two copies of the common A allele upstream of the CAPZB gene. In genome-wide association studies, this genotype is associated with higher average serum thyrotropin (TSH) levels compared to carriers of the minor G allele. This finding reflects typical polygenic variation in the pituitary-thyroid axis rather than a clinical diagnosis of thyroid dysfunction.
Carried by approximately 60% to 70% of individuals of European ancestry and roughly 75% to 80% of individuals of East Asian ancestry.
Slightly lower baseline TSH
You carry one copy of the minor G allele near the CAPZB gene. Research indicates that each copy of the G allele is associated with a modest decrease in circulating thyrotropin (TSH) levels relative to the AA genotype. The overall clinical impact of this variant alone is very small, accounting for only around 1% of normal population variance in thyroid hormone regulation.
Carried by approximately 25% to 35% of people of European ancestry and about 20% of East Asian populations.
Lower baseline TSH levels
You carry two copies of the minor G allele near the CAPZB locus. In population cohorts, individuals with the GG genotype have shown an average decrease in baseline serum TSH of approximately 0.4 to 0.5 mU/L compared to individuals with the AA genotype. Because thyroid regulation is influenced by many genetic and environmental factors, this statistical association does not imply abnormal thyroid function on its own.
Carried by roughly 2% to 5% of individuals of European ancestry and fewer than 2% of people of East Asian ancestry.
Understanding the Variant
The variant rs10917469 is a specific change in the DNA sequence located on chromosome 1p36.13. In genetics, a single nucleotide polymorphism (SNP) like this represents a variation at a single position in the genome. This particular SNP is situated in a linkage disequilibrium block approximately 10 kilobases upstream of the transcription start site for the CAPZB gene. Because it sits in a region where DNA is inherited together, it is possible that the observed associations with biological traits are due to the variant's influence on the regulation of nearby genes, rather than the CAPZB gene itself. Scientists use these markers to study how small differences in our genetic code correlate with measurable physiological traits across large populations.
The Role of CAPZB
The CAPZB gene provides instructions for creating the beta subunit of the F-actin capping protein. This protein is a critical component of the cytoskeleton, the internal framework that gives cells their shape and structure. By binding to the fast-growing, or 'barbed,' ends of actin filaments, the protein prevents the addition or loss of subunits, effectively stabilizing the length of these filaments. This process is essential for maintaining cell morphology and coordinating intracellular transport in both muscle and non-muscle cells. While CAPZB is expressed in thyroid and pituitary tissues, its direct role in thyroid function remains a subject of ongoing investigation. Current evidence suggests that while the SNP is physically near this gene, the biological mechanism linking the variant to thyroid traits is not yet fully understood.
Research and Evidence
The association between rs10917469 and serum TSH levels was first identified through a genome-wide association study (GWAS) involving thousands of participants. Researchers observed that the G allele of this variant was associated with a decrease in serum TSH concentrations. This finding was subsequently replicated in independent community-based studies, providing statistical support for the link. However, it is important to note that the evidence strength for this association is considered limited. While the statistical signal reached genome-wide significance in initial studies, the functional pathway—how exactly this DNA change influences TSH levels—remains unclear. Because the variant is located in a region with multiple genes, researchers caution that the association might be driven by regulatory effects on other nearby genes rather than CAPZB itself.
Population Frequency
Genetic variants are distributed differently across global populations, and rs10917469 is no exception. Data indicates that the minor allele frequency for this variant is approximately 0.22 in European populations and 0.12 in East Asian populations. These frequencies represent the proportion of the population that carries the less common version of the DNA letter at this specific site. Understanding these frequencies is a standard part of genomic research, as it helps scientists determine if a genetic association is consistent across different ancestral backgrounds. Because frequency can vary significantly, findings observed in one population may not always be replicated in another, highlighting the importance of diverse genetic studies in building a comprehensive understanding of human health.
Interpreting Your Results
If you have received information about your genotype for rs10917469, it is important to view it within the context of current scientific limitations. This variant is associated with statistical trends in TSH levels, but it is not a diagnostic tool for thyroid disease or any other medical condition. Thyroid function is a complex trait influenced by a wide array of genetic, environmental, and lifestyle factors. A genetic association does not imply a direct cause-and-effect relationship, and having a specific genotype does not guarantee any particular health outcome. If you have concerns about your thyroid health or hormone levels, you should consult with a qualified healthcare professional. They can order appropriate clinical tests, such as blood work, which provide the necessary data to assess your health status accurately. Never use genetic information to make decisions about medication or treatment without professional medical guidance.
How common is this variant?
The minor allele frequency for rs10917469 is approximately 0.22 in European populations and 0.12 in East Asian populations.
Frequently asked questions
Is rs10917469 a test for thyroid disease?
No, rs10917469 is not a diagnostic test for thyroid disease. It is a genetic variant identified in research studies as being statistically associated with variations in TSH levels, but it does not predict or diagnose clinical conditions.
What does the CAPZB gene do?
The CAPZB gene encodes a protein that stabilizes actin filaments within cells. This structural support is vital for maintaining cell shape and facilitating transport processes within the cell.
Should I change my medication based on this result?
No. You should never change your medication or treatment plan based on genetic information. Always discuss your health, medications, and any genetic findings with your doctor or pharmacist.
Why is the evidence for this variant considered limited?
The evidence is considered limited because while there is a statistical association with TSH levels, the biological mechanism explaining how this variant influences thyroid function is not fully understood. Additionally, the variant is in a region with multiple genes, making it difficult to pinpoint the exact cause.
Sources & further reading
Educational information only, last refreshed 10/19/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs10917469?
Upload a raw DNA file from 23andMe, AncestryDNA, MyHeritage, or FamilyTreeDNA and see this variant — plus thousands more — interpreted in your full report.
Get my report — $29